Diagnosis. In this and the next species, there is little sexual dimorphism of forewing features, but hemusalis Walker is generally much larger with the red medial band more darkly suffused in males; this sex can easily be distinguished by a conspicuous ovate black spot centrally, subbasally on the hindwing. The male forewing is unmodified and both sexes have the medial area rufous (see also the female of moloalis Walker below). The male labial palps are much more robust in hemusalis with a tuft of scales at the junction of the second and third segments. The male genitalia of lentalis have a rather rounded, spined ventral process to the valve, and an angular projection at the centre of the ventral margin whereas this process is narrower, tapering in hemusalis, but still with a projection within the ventral margin. The dorsal process is finely spined apically in lentalis but has fewer, more prominent spines in hemusalis. In the female, the ductus is short in relation to the bursa. It is relatively longer in hemusalis, which has distinctive spined, foliose processes on each side of the ostium (somewhat obscured in Fig. 192).
Taxonomic note. The synonymy of this species was revised by Owada (1992), with illustration of type material. However, Edwards in Nielsen et al. (1996) revived metisalis to specific status without comment, with turbidalis as a synonym. The male genitalia of Oriental and Australian specimens show no significant differences.
Geographical range. Indian Subregion to Japan (Owada, 1987; as repugnalis) and Sundaland, Sulawesi, Australia.
Habitat preference. Only five specimens from Borneo have been identified as lentalis, a female from Ulu Dusun in the lowlands of Sabah and another from 600m on G. Trus Madi. Single males without altitude data have been located from G. Kinabalu and Sarawak. The type material of repugnalis was taken in Sarawak, probably also in the lowlands, by A.R. Wallace. It is probably a lowland species that persists in disturbed habitats.
Biology. Sugi (1987) illustrated the larva of lentalis (as repugnalis). It is a medium greenish brown that is variegated with paler longitudinal dashes in a darker network.
The larva feeds on dead foliage in Japan, and Robinson et al. (2001) listed dead grass material.
